📌 Introduction

One of the most common scenarios in personal computing remains the installation of multiple operating systems on the same machine, particularly a Windows + Linux dual-boot. On modern Linux distributions like openSUSE Tumbleweed, the GRUB bootloader plays an essential role in allowing the user to choose which system to boot.

To automatically detect other operating systems (like Windows), the os-prober command is often used. However, its behavior can raise technical questions, especially since in 2025, important security changes have modified its default operation.

1. 🔍 What is os-prober?

1.1 Operation

To use os-prober manually, open a terminal and run:

sudo os-prober

When launched, os-prober:

2. 🧠 The message: "DM multipath kernel driver not loaded"

When running os-prober, it may display a line like:

261412.743223 | DM multipath kernel driver not loaded

⚠️ In 99.9% of cases, a Windows system installed on a personal PC does not rely on multipath storage.

3. 🆕 NEW 2025: Mandatory GRUB_DISABLE_OS_PROBER Configuration

3.1 🔧 Typical symptom

After a system or kernel update, you regenerate GRUB:

sudo grub-mkconfig -o /boot/grub/grub.cfg

And get this result:

Warning: os-prober will not be executed to detect other bootable partitions.
Systems on them will not be added to the GRUB boot configuration.
Check GRUB_DISABLE_OS_PROBER documentation entry.

3.2 ✅ Mandatory solution

sudo nano /etc/default/grub

GRUB_DISABLE_OS_PROBER=false

3.3 ✅ Success confirmation

Warning: os-prober will be executed to detect other bootable partitions.
Its output will be used to detect bootable binaries on them and create new boot entries.

4. 🧪 Case study: openSUSE Tumbleweed and os-prober

4.1 🔧 Context

A user runs the command:

sudo os-prober

And gets:

261412.743223 | DM multipath kernel driver not loaded
/dev/sda2:openSUSE Tumbleweed:openSUSE:linux:btrfs:UUID=...:subvol=@/.snapshots/1/snapshot

4.2 📋 Interpretation

5. ❓ Why doesn't os-prober detect Windows?

There are several legitimate reasons why an installed Windows system may not appear in os-prober's output.

grub-mount: error while loading shared libraries: libfuse3.so.3: cannot open shared object file

# Check for grub-mount
which grub-mount || echo "grub-mount not installed"

# Test for missing library
ldconfig -p | grep libfuse3

ldconfig -p | grep libfuse3

# Search if the library is present
sudo find / -name libfuse3.so.3 2>/dev/null

# Install apt-file if necessary
sudo apt update
sudo apt install apt-file
sudo apt-file update

# Search for package containing libfuse3.so.3
apt-file search libfuse3.so.3

# Use dnf to find the package
sudo dnf provides */libfuse3.so.3

# On older versions with yum
sudo yum provides '*/libfuse3.so.3'

# Update package database
sudo pacman -Fy

# Search for package containing the library
pacman -F libfuse3.so.3

# Use zypper to find the package
zypper search --provides --match-exact 'libfuse3.so.3'

# Or use rpm directly
rpm -q --whatprovides libfuse3.so.3